Suddenly one of the sprinkler system zones does not stop when time expires. It remains open. I had to manually shut off water supply after time for all zones expire. Any help will be appreciated.
Thanks.

Just got a 24 ' above ground pool installed. The guys who installed it put it right over a sprinkler head, which 3 weeks later finnally burst through. Now water is entering the sprinkler system and pouring out another head. Installation company says their contract states they are not responsible...